Seal assembly



Allg 5, 1952 W. J. BORCHARDT `2,605,994

SEAL ASSEMBLY v Filed 0G11. 5l, 1945 l//LL /HM Josef/f 50M/,mor

Patented ug. 5,

SEAL ASSEMBLY William Joseph Borchardt, Los Angeles, Calif., as` v signor to Thompson Products, Inc., Cleveland, l Ohio, aV corporation of Ohio Y Y Y Application october 31, 1945, serial No. 625,831A

This invention relates to port seals and the like which are easily inserted into position and readily accommodate expansion and contraction without lessening sealing eficiency.

Specically the invention deals with seals for plug valves and the like such as rotary selector valves.

According t this invention there is provided a tubular member for insertion in the port of a valve or the like and having an end face for sealingly engaging a movable valve member such as a plug adapted to control ilow through the port. Thev tubular vmember has an internally grooved outturned flange at one end thereof adapted to be readilyseated in an internal groove surrounding the port.A The groove in the ange receives a snap ring which sealingly anchors the ange in the groove of the port. The other end of the tubular member is thickened to provide a relatively wide end rim or sealing face for sealingly engaging the valve member or plug. This endface is contoured to nt around the valve member. The thickened portion preferably is rigid and a metal insert ring can be imbedded therein. The inner end of the thickened portion provides an internal shoulder spaced axially from the flange portion of the tubular member. A flexible tubular portion integrally connects the flanged end and the thickened end of the tubular member. A spring is held under compression between the snap ring and the shoulder ln the tubular member and functions to urge the sealing end face of the member against the valve or plug. The flexible intermediate portion of the tubular member between the ange and the thickened portion is normally bowed inwardly from the port wall to accommodate movement of the sealing end face away from the anchored ange portion of the tubular member and thereby readily allow expansion of the assembly to accommodate wear or shrinkage of the sealing end face of the tubular member. In the event of expansion of the sealing end' face of the tubular member the flexible tubular portion will assume a more inwardly bowed position. In this manner, the seal assembly of this invention has an anchored end portion and an axially movable opposite end portion.

It is, then, an object of the invention to provide an inexpensive, easily assembled, and eillcient seal construction for ports and the like.

A still further object of the invention is to provide Aa seal assembly having an anchored end portion 'and an axially lmovable endportion.

A still further object of the invention is to provide "a seal assembly for plug valves and the like 1 Claim. (Cl. 251-113) composed of a tubularl member having a sealing end face, an internal shoulder intermediate the ends of the tube, an outturned flange at the end of the tube remote from the sealing end face, a rigidring for locking the ange to a port, and a coil spring interposed between the rigid ring and the internal shoulder.

A stillfurther object of the invention is to providea seal assembly forplug valves and the like having a first end portion anchored against axial movement, a second end portion adapted to move axially relative to the rst end portion, and a spring interposed between the first and second end portions for urging the second end portion away from the rst end portion.

A still further object of 'the invention is to provide a port seal for valves and the like embodying a tubular'member adapted to be readily inserted in a port for presenting asealing end face to avalve or the like and having an outturned internally grooved flange spacedfrom the sealing end face and arranged to be sealingly anchored to the port. l

A still further object of the invention is to provide a port seal for an internally f irooved` port wherein the seal is equippedwith an outturned internally grooved flange for seating in the groove of the port and for vreceiving a rigid locking rim to hold the ange in sealing engagement in the groove of the port. 1

Otherand further objects of the invention will be apparent to those skilledin the art from the following detailed description of the annexed sheetof drawings which, by way of preferred example only, illustrates one embodiment of the invention.'

Onthedrawings:

Figure 1 is a fragmentary lvertical cross-sectional'view of a selector .valve 0r shutfoi cock em- Ilo'odying a seal assembly according tothisinven- Figure@ Yisa fragmentary horizontal crosssectional view, taken along the line II-II of Figure 1, but illustrating the plug of the valve in port-closing position.

Figure 3 is an-exploded vertical cross-sectional view of the seal of this invention, illustrating the seal parts in spaced axial alignment for assembly.

As shown on the drawings: y

In Figures land 2 the referencel numerallii designates generally a valve having a body member il providing an operating chamberlZ and equipped with a laterally extending nipple portion l la defining a cylindrical port |73 communieating with the valve-operating chamber l2 at its inner end. A cover I4 is provided on the body member and is sealed thereon by means of a gasket I5. A cylindrical plug valve I6 is rotatably mounted in the valve-operating chamber I2 on graphitic carbon bearing rings I1. The valve I6 has a cylindrical bore |6a therethrough adapted to register with the port I3. In addition, the valve I6 has a cylindrical peripheral wall Ib held in spaced relation from the operating chamber I2 by the bearing rings II and adapted to span the port I3 whenever the valve is rotated to move the bore |6a therethrough out of registration with the port. It should be understood,

of course, that the valve has an operating post 'i (not shown) extending through the cover I4 sol that the valve can be rotated in the chamber I2..

The port I3 has an internal groove |3a there-r around spaced axially outwardly f rom the oham-V ber I2 of the body I I. This groove |3a is pref erably provided with a flat cylindrical bottom -f Wall and straight spaced parallel side walls.

In accordance with this invention La Vrubber tubular member If8: is seatedl in the port, I3. The tubular member I8' has an outturned ange I8c at one end thereof'for snugly iitting in the groove i3d of the port. This iiange I8c-'preferably has a flat cylindrical outer rim andspaced opposed straight parallel side wallsfso. that theirim will t on the at bottomofthe'groove and| so that the side walls Vwill hug the sidev walls of the groove. Theange ISa-has an' internal groove I8b therearound preferably midway between the side walls. of the flange and terminating inwardly from the rim of the iiange tovleave walls of substantial thickness surrounding the. groove.

The opposite end of thed tube |8f is thickened anddeiines a dished or concavesealing end face I8c for itting around a portion of the'wall IS-b of the valve I6'. The. thickened portion of the tube extends inwardly'of thetube to'. terminate in an internal shoulder I8d intermediate the ends of the tube. A rigid ring ISIy of metal or rigid plastic material is imbedded in the thickened portion of the tube but is completely covered with rubber. This imbedded ring- I9 has a flat end wall Illa spaced inward from the shoulder Id and backing up the shoulder to render itsomewhat' rigid. The oppositeendf of thering has a'dished or concave end face lbispaced inwardly from the end face I8c of the tube to back up this end'face and render it somewhat rigid. It shouldbe-under` stood, however; thatthe shoulder |8d' and the end face I8c areresilientlyi deformable to alimited extent but the end faces of the ring I9 prevent unlimited deformation of the rubber end face I8c and shoulder |8d; The arrangement is preferably such that an even covering of-rubber is provided for both end faces Illa and IBb of the ring and for this purpose the end -faces of the ring have the same configuration as the end face I8c and shoulder I8d of the tube.

The tube I8 has a relatively limp and flexible intermediate integral portion |8e joining the flange I8c and the thickened portion at the other end of the tube. o v y The outer diameter of the main body of'the tube I8 is slightly smaller than the diameter of the port I3 so that the tube will slidablyfit in the port.

A tubular coil spring 2U is inserted in the tube I8 and is bottomed therein on the'shoulder Id. The diameter ofthe coil spring is less than the inside diameter of the portion I8c of the tube but greater than the inside diameter of the thickened portion of the tube.

A flat metal or plastic snap ring 2|, sized to t in the groove I8b of the flange I8a, is provided for locking the flange in the groove |3a of the port and for providing an abutment for the opposite end of the coil spring 20. The snap ring 2| has a gap 2Ia therein and can be contracted so as to be readily inserted in the groove I8b of the flange |8a. When the ring is released it will expand to secure thel ilange I8c in the groove |3a of the port. The inside diameter of the ring 2| is less than the inside diameter of the tubular portion I8c to provide an abutment for the spring 20.

tube in the. port to be bottomed on the shoulder IBdand the snap ring is then inserted in the groove I8b of the iiange I8a to compress the spring 20 and to sealingly lock the flange IBa in the groove ISa of the port. The tube I8 is preferably longer than the distance between the wall IGb of the valve I6 and the groove I3a of the port I3 so that the ii'exible tubular portion I8e will be slightly bowed inwardly as shown in Figures 1 and 2 when the assembly is in position. This inward bow of the tubular portion I8c accommodates elongation of the assembly to maintain the end face I8c in sealing engagement with the wall |81) of the valve with a pressure determined by the spring 20. In this arrangement, wear or shrinkage of the end face I8c of the tube I8, or tolerance variations in the assemblywill not interfere with the maintenance of sealing` engagement between the end face of the tube and the peripheral wall ISD-of the valve. Since, in addition, the portion Ievof the tube is relatively limp, it can b e bowed iurther'inwardly to accommodate expansionof` thev sealing end face I8c or opposite tolerance variations in the assembly.

From the above descriptions it willbe understood that the invention `providesan assembly having an axially moving sealing end face and an axial-ly locked opposite end flange with a spring or other resilientV means constantly urging the sealing end face away from the locked end to maintain a desired sealing pressure between` the sealing-end face and the part to be. sealed. It'will also be understood that the seals, ofthis invention are readily inserted; into ports or thef like of a valve without removing the valve from itshousing. Replacementlof` seals in valves or the iikeis thereby-facilitated.'

- It wi-lLof course, be understood that various details of construction may be varied through a widel rangewithout departing from the principles oi-Y this. invention and it is,vtherefore,A not4 the purposetolimit; the patent grantedhereon otherwise thannecessitated by the scope ofthe appended' claim.

I claim as' my invention:- Y In a fluid-flow control device 'comprising a r0- tary plug valve including a body having a valve port. the improvement of a self-adjusting sealingA device f orthe valve port comprising, ayexible generally tubularly conformed sleeve having an outturned; sateliet-forming;V :Bange on oneendA adapted to overliea portion oiA the valve body adjacent the Valve port, said flange havingr a cylindrical outer rim and spaced.. opposed straight parallel side walls, the opposite end'oijsaidsleeve having an inwardly extending thickened portion providing an, internal annular shoulder intermediatey the ends of the sleeve, a first rgidlring 5 embedded in said thickened portion to back up said internal shoulder, the end face of said thickened portion being curved to conformingly engage lthe plug of the valve, a second rigid ring in said flange between said side walls, Said second ring having an inside diameter less than the inside diameter of said sleeve, and a coil spring in said sleeve bottomed against said second ring and against said internal shoulder to resiliently'load the end face of the sleeve.

WILLIAM JOSEPH BORCHARDT.

REFERENCES CITED The following references are of record in the le of this patent:

Number in Number 6,. UNITED STATES PATENTS Name Date Wallgren Aug. 25, 1942 Melichar 1 Sept. 4, 1945 Snyder Jan. 1, 1945 Snyder July 30, 1946 Loftis Sept. 12, 1950 FOREIGN PATENTS Country Date Great Britain Jan. 10,1939 

